Because it has lost its wormhole navigator, the small terrestrian space ship is disoriented wandering around. The crew of the Mercurius Quarbis discovers a forgotten space colony, has a very unpleasant encounter with a time-devouring world-spawner and owns it to the shipboard choir that it finally gets on Half Planets a real chance to find its way back to Earth. The navigator, just to mention it, is purchased and resold by aliens, but nevertheless gets to Earth first …

The stories about these adventures are told by different narrators: the extraterrestrial “mind listener” Breg’cl’orileino and the initially leg wise disabled robot RX1950364, the cranky captain Schneider, the missing navigator Kemeny and others.